This standard is issued under the fixed designation C42/C42M; the number . of core test results.2 and that is free of is the individual responsible for analysis or. ASTM C42/C42M () Standard Test Method for Obtaining and Testing Drilled ASTM International, West Conshohocken. Free SCIRP Newsletters>> . ASTM C Potential Resistance to Degradation. In-situ Tests . Determine time from start until no free water is on ASTM C42, Coring, 3 cores/5, sf.

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If time permits, the concrete should not be removed before it is 14 days old. For strengths above psi [70 MPa], test data on cores show that the correction factors may be larger than the values listed above.

It is the responsibility frde the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

When capping is employed the caps shall be as thin as practicable and shall be formed of high-strength gypsum plaster. The saw shall have a diamond or silicon-carbide cutting edge and shall be capable of cutting specimens which conform to the prescribed dimensions, without excessive heating or shock.

Livro sobre Cimento Portland e Concreto. If the ratio of the length to the diameter of the core specimen exceeds 2. A number in parentheses indicates the year of last reapproval. SI units are shown in brackets. Therefore, results of two properly conducted tests on cores sampled from the same hardened concrete where a single test is defined as the average of astmm observations coreseach made on separate adjacent drilled 4 in.

ASTM CC42M – 04 – Free Download PDF

The preferred length of the capped specimen is between 1. NOTE 3—Correction factors depend on various conditions such as moisture condition, strength level, and elastic modulus. When the line of contact is not straight or contains projections or depressions having heights or depths greater than 0. Cap or grind the cores, and test them within 48 h of receipt. They are applicable to both dry and wet concrete for strengths between and psi [14 to 42 MPa]. Parte 1 de 2 Designation: Cores for Compressive Strength 7.


Average values are given in the table. ACI provides core strength acceptance criteria for new construction. Core specimens with length-to-diameter ratios less frer 1.

C42-Obtaining and Testing Drilled Cores and Sawed Beams of Concrete

A superscript epsilon e indicates an editorial change since the last revision or reapproval. Thus, these factors should be applied to high-strength concrete with caution.

Additionally, this method may be used to provide strength information on older structures. Length of Drilled Cores 6. Current edition approved Feb. Measure core diameters to the nearest 0. BoxFarmington Hills, MI Do not use specimens with projections or depressions greater than 0.

If this is not practical, removal of concrete can proceed if the cut surfaces do not display erosion of the mortar and the exposed coarse aggregate particles are embedded firmly in the mortar. The values stated may not be exact equivalents, therefore each system must be used independently of the other. Last previous edition C 42 — In-place test methods may be used to estimate the level of strength development prior to attempting removal of concrete samples.

Measure the lengths of such cores in accordance with Test Method C C 39 with the addition of the following information: Sampling and sample preparation requirements are given to ensure that dimensional requirements are met and that the specimens are comprised of intact sound concrete as free of flaws as the particular structure will allow.

Core diameters less than 3. Significance and Use 3. The ends shall be sawed or ground to tolerance or capped in accordance with capping procedures for hardened concrete specimens of Practice C Originally published as C 42 — 21 T.


ASTM C42-C42M – 04

The relationship is affected by many factors such as the strength level of the concrete, the in-place temperature and moisture history, and the strength gain characteristics of the concrete. If necessary, saw the ends of the specimens until the following requirements are met: Ends are not to be capped. This standard has been d42 for use by agencies of the Department of Defense. NOTE 1—It is not possible to specify a minimum age when asrm is strong enough to withstand damage during removal, because the strength at any age depends on the curing history and strength grade of the concrete.

Combining values of the two units may result in nonconformance. When preparing strength test specimens from samples of hardened concrete, samples that show defects or samples that have been damaged in the process of removal shall not be used. NOTE 2—Prior to capping, the density fref a core may be determined by weighing it and dividing it by the aetm calculated from the average diameter and length, or by any other standard method for determining density.

A specimen taken perpendicular to a vertical surface, or perpendicular to a surface with a batter, shall be taken from near the middle of a unit of deposit when possible and not near formed joints or obvious edges of a unit of deposit. The acceptance criteria for core strength is to be established frfe the specifying authority.

Determine the average diameter by averaging two measurements taken at right angles to each other about the midheight of the specimen.

When grinding or capping of the bearing surfaces is.